my display is not working, and the batery heats a lot

i bought a sansa fuze 3 weeks ago, and now my mp3 is not working. my display is not bright. when i turn on mp3 player, it works, but it takes 3-4 seconds to see the file name on display. and when i turn next song it became dark again and turns on in 3-4 seconds.

when i conect my mp3 to laptop, it charges but it becomes xetremely hot.